1. Technical Field
This application relates to a surgical device for removing tissue and more particularly relates to a surgical tissue biopsy device insertable through a small incision in the body.
2. Background of Related Art
Over 150,000 women in the United States alone are diagnosed each year with breast cancer. A biopsy of breast tissue is indicated when a breast abnormality is found, allowing removal of the tissue and testing to determine whether the abnormality is malignant and further surgery is necessary. Early diagnosis and removal of cancerous tissue is critical for successful treatment as early detection greatly increases the chances of survival.
Numerous devices are currently available for performing breast biopsies. These devices function to dissect a portion of the breast tissue and remove it from the body for pathology to determine whether the tissue is malignant.
The most invasive procedure is referred to as open excisional biopsy. In this procedure, large tissue samples are surgically removed, requiring long recovery times, risking disfigurement of the breast, increased scarring and increased morbidity.
In an attempt to overcome the disadvantages of open surgery, more minimally invasive instruments have been developed. One minimally invasive approach utilizes a percutaneous instrument referred to as a fine needle biopsy instrument. In this instrument, a needle and syringe are inserted directly through the breast into the target tissue, e.g. the lump, to remove a cell sample for pathology. One disadvantage of this technique is that numerous cell samples are required to be taken from the tissue to obtain a sufficient mass for testing, thereby requiring numerous needle sticks and increasing the time required for the procedure. Another disadvantage is that careful locational tracking of the tissue cells removed is required for accurate analysis. Also, with these devices there is a greater potential for false negatives due to the small sized specimens being removed without removal of sufficient surrounding areas of healthy tissue for comparison.
Another type of minimally invasive device is referred to as core needle biopsy. This device has a spring actuated cutter and obtains a larger specimen than the fine needle biopsy instruments. The specimen is suctioned into a side window in the needle and then back through the proximal end of the needle. Although larger than fine needle biopsy instruments, these needles are still relatively small, e.g. 2 mm in diameter. Since typically removal of between five and twenty tissue cores of 2 mm in diameter and 20 mm in length is required for accurate pathology, five to twenty needle sticks into the patient of this 2 mm diameter needle is required. These devices also have the disadvantage that the spring force cutting action may displace malignant cells into the adjacent normal tissue. Also, the amount of false negatives can be high because of inadequate removal of surrounding healthy tissue. Like fine needle biopsy, success and accuracy of the procedure is skill dependent because the device must be maneuvered to various positions and these different positions accurately tracked.
Another disadvantage common to both fine needle and core needle biopsy devices is that the entire lesion cannot be removed. Therefore, if the tests show the lesion is malignant, another surgery must be scheduled and performed to remove the entire lesion and surrounding tissue. Besides the additional cost and surgeon time, this can have an adverse psychological affect on the patient who must await the second surgical procedure.
Some percutaneous devices, such as the Mammotome marketed by Ethicon, Inc., attempted to overcome some of these disadvantages of percutaneous devices by enabling multiple specimens to be removed with a single needle stick. The specimens are removed from the proximal end of the needle by a vacuum. Although overcoming some disadvantages such as reducing the number of needle sticks, the Mammotome still fails to overcome many of the other drawbacks since careful tracking is required, success is skill dependent, and a second surgery is necessary if the lesion is malignant, with the attendant expenses and trauma.
In an attempt to avoid a second procedure, the ABBI instrument marketed by United States Surgical Corporation provided a larger needle so that the entire specimen and tissue margins could be removed. The extra tissue excised is achieved by a larger diameter cannula. The cannula removes breast tissue from the skin surface entry point to the interior region of the breast where the lesion is located. The advantage of this instrument is that if pathology indicates the tumor is malignant, then an additional surgical procedure is not necessary since the tumor and margins were removed by the large cannula. However, a major disadvantage of this instrument is that if pathology indicates the lesion is benign, then a large tissue mass would have been unnecessarily removed, resulting in more pain, a larger scar, and possible disfigurement of the breast. Thus, ironically, the instrument is more beneficial if the tumor is malignant, and disadvantageous if the tumor is benign. In either case, the instrument has the further disadvantages of causing additional bleeding because of the large incision and requiring closure of a larger incision, thereby increasing scarring, lengthening patient recovery time, and adding to the cost, time and complexity of the procedure.
It would therefore be advantageous to provide a surgical breast biopsy device which can access the targeted lesion through a small incision but be able to remove the entire lesion and margin, thereby avoiding the necessity for a second surgery. Such device would advantageously reduce the risk of cancer seeding, provide more consistent testing, reduce surgery time, reduce bleeding, and minimize disfigurement of the patient""s breast.
The present invention overcomes the foregoing deficiencies and disadvantages of the prior art. The present invention provides a surgical biopsy apparatus for cutting tissue comprising a housing having a longitudinal axis, first and second members movable from a retracted position to an extended position with respect to the housing, a third member slidably positioned and extendable with respect to the first member, a fourth member slidably positioned and extendable with respect to the second member, and an electrocautery cutting wire movable with respect to the third and fourth members to surround a region of tissue positioned between the third and fourth members to cut the tissue.
The apparatus preferably further includes a tissue retrieval bag movable with respect to the third and fourth members and movable from a retracted position within the housing to an extended position distally of the housing to surround a region of tissue positioned between the third and fourth members to remove the cut tissue.
The apparatus preferably further comprises a first carrier slidably positioned over the first and third member, wherein the first carrier supports and advances the electrocautery wire and a suture for closing the tissue retrieval bag.
Preferably the first and second members move radially outwardly away from the longitudinal axis of the housing and the third and fourth members initially move radially outwardly away from the longitudinal axis followed by movement inwardly towards the longitudinal axis. The third member is preferably telescopingly received within a first channel in the first member and the fourth member is preferably telescopingly received within a second channel in the second member.
The present invention also provides a surgical biopsy apparatus for cutting a tissue mass comprising a housing, a plurality of first members extendable with respect to the housing and movable in a first direction at a first angle to the longitudinal axis of the housing, a plurality of second members movable with respect to the first members in a second direction different than the first direction and at an angle to the first angle, and a cutting wire movable longitudinally with respect to the first and second members to cut the tissue mass.
The apparatus preferably includes a tissue retrieval bag movable longitudinally with respect to the first and second members to remove the tissue mass cut by the cutting wire. Preferably, a loop of the cutting wire and a mouth of the tissue retrieval bag are enlarged by the plurality of first and second members.
The apparatus may include a marker supported within the housing and insertable into the tissue mass, the marker composed of shape memory material and the first and second members surrounding the marker. The first and second members may also be composed of shape memory material.
The present invention also provides a surgical biopsy apparatus comprising a housing, a plurality of members advanceable with respect to the housing to provide a boundary for an area of tissue to be removed, a cutting wire loop advanceable with respect to the plurality of members to cut the area of tissue and/or a tissue retrieval bag advanceable with respect to the plurality of members to remove the area of tissue. Preferably, the cutting wire loop and/or a mouth of the tissue retrieval bag is moved to a larger diameter as it is advanced with respect to the members. Preferably at least one carrier is provided which is advanceable over one of the plurality of members to advance the cutting wire and the tissue retrieval bag toward the target tissue.
The apparatus may also include an ultrasonic transducer at a distal end of the housing to enhance ultrasound imaging during the biopsy procedure.
The present application also provides a method for removing a tissue mass for biopsy comprising inserting a cannula to a position proximal of the target tissue mass, advancing a plurality of tissue penetrating members from the cannula to an angular position to create a boundary area around the tissue mass, and advancing an electrocautery cutting wire with respect to the tissue penetrating members to surround the tissue mass defined within the boundary area.
The method may further comprise the step of advancing a tissue containment bag with respect to the tissue penetrating members to encapsulate the cut tissue mass for removal, wherein the cutting wire and tissue containment bag are advanced substantially simultaneously.
A method for performing breast biopsy is also provided comprising inserting into breast tissue a housing having a diameter smaller than a diameter of the tissue to be biopsied, advancing penetrating members through the breast tissue to create a tissue boundary area having a transverse cross-sectional length greater than the diameter of the housing, and advancing a cutting wire so a loop of the cutting wire moves to a diameter greater than the diameter of the housing.